Sponsored: Casio’s G-Shock GM-B2100 Offers Excellent Shock Protection

The latest addition to the full-metal G-Shock lineup is the GM-B2100. The release is more than simply a conversion of the GA-2100, one of the hits of recent years, into a full-metal version. The craftsmanship and attention to detail in evidence in the new model contain evidence of how the design and functionality of the series continue to evolve, as well as hints for what the future may hold.

Photographs by Yu Mitamura
Text by Yuzo Takeishi

Released in 2019, the GA-2100 (right) proved a worldwide hit, with its octagonal bezel giving it a distinctive appearance and usability. The original iteration is now joined by the GM-B2100 (left), which brings a full-metal overhaul to the appearance of the watch as well as featuring further evolutions to design details and functions.

The GM-B2100 marks the latest addition to the full-metal series. Its exterior design is practically the same as the design of the previous three models. Resin versions of the G-Shock are produced by injection molding, in which resin is injected into a metal mold. In the full metal series, however, the watches are made by pressing and forging stainless steel plates. The complex shape of the G-Shock watches means they cannot be produced in a single press, and the full metal series uses more than 10 pressing stages. Other processes, including annealing and polishing, are carried out between each pressing. These are repeated more than 10 times before the application of the final polishing process, so that the manufacture of the watch exterior takes a considerable amount of time.

(Left) GM-B2100D-1A , (Center) GM-B2100BD-1A, (right) GM-B2100GD-5A
The third installment in the full metal series, incorporating a stainless steel cladding on the basis of the GA-2100 model with octagonal bezel that appeared in 2019. The silver and black models use a single black tone for the dial, maintaining the cool and stylish image of the 2100 series. Tough Solar gives around 18 months on a full charge (power save mode). Stainless steel case (49.8 x 44.4 mm).

When the idea of a full-metal version of the G-Shock was first raised seven years ago, Casio immediately knew that the biggest challenge would be to come up with a design that would guarantee the shock resistance expected of a G-Shock watch. In the end, Casio had to redesign the entire internal structure of the watch from scratch. Although stainless steel is more resilient to shock than the resin materials used in most G-Shock watches, its higher specific gravity means that the watch sustains a considerable shock if it is dropped.

After considerable trial and error, the company finally arrived at a fundamentally different shock resistance structure from that used in conventional resin models. Absorbent cushioning made of fine resin is set between the center case, which protects the module, and the stainless steel top bezel. This acts as a damper and protects the watch even from strong shocks if the watch is dropped. This design successfully protects the module that is the heart of the watch.

The shock resistance structure in the full metal series: the black components made from fine resin are placed on top of the center case (the cylindrical black part) that protects the module that is the heart of the watch, before the stainless steel top bezel is stacked on top of this. The fine resin parts act as cushioning, protecting the module from external pressure and shock.

Another improvement in the full metal version of the watch involved the attachment between the case and bracelet. In resin G-Shock watches, the case and bracelet are connected by two prongs, but the full-metal model uses a new three-pronged lug structure. With the two-pronged structure, there was a risk that the connecting pipe joining the case and the bracelet might buckle under the impact of a shock if the watch were dropped. Increasing the number of prongs disperses shocks to the connecting pipes and button shafts.

The full-metal models of the G-Shock feature an altered lug design that incorporates three prongs joining the case to the bracelet. This disperses shocks to the connecting pipes if the watch is dropped, and was specially created for the full-metal model in order to reduce the risk of buckling and distortion to the connecting pipes and button shafts.

The GM-B2100 incorporates the same shock resistance structure. While using the same screw-lock case back that is shared by all the full-metal G-Shock watches, by paring away flab from the center case and the inner edge of the top bezel and shrinking the clearance between the top surface of the bezel and the glass face, the design successfully gives the latest model the distinctively slim appearance and dimensions of the 2100 series. In fact, the new watch has the thinnest dimensions yet seen in the full-metal series, at just 12.8mm, just 1mm thicker than the GA-2100—eloquent testimony to the remarkable dedication shown by the design team in balancing the competing aims of shock resistance and streamlined dimensions.

Connectivity With a Focus on Practicality and Function

Of course, the GM-B2100 not only combines excellent shock resistance with a robust appearance. It also comes with the complete range of practical functions typical of G-Shock watches. Perhaps most noteworthy are the Mobile Link/Application Link functions. By connecting to a smartphone via Bluetooth, these allow the watch to correct itself automatically according to precise data obtained from the smartphone. The watch is also compatible with World Time settings for nearly 300 cities, making it possible to check the time immediately in a pre-set city on the watch.

(Left) Like previous iterations in the full metal series, the GM-B2100 comes equipped with Mobile Link functionality, and Bluetooth connectivity. Setting of accurate time and World Time settings can be done easily via the dedicated Casio Watches app.
(Right) The watch incorporates back-lighting using high luminance double LEDs for excellent readability even in the dark.

The watch can also provide reminders of appointments made with the dedicated CASIO WATCHES smartphone app, and also comes with a handy “phone search” function. As mentioned above, the GM-B2100 features Tough Solar power. In terms of power, the watch is a truly reliable partner: On a full charge the watch can be used for approximately seven months, even with low exposure to sunlight, and for up to 18 months in power-save mode.

The GM-B2100 has a sturdier and more robust feel than ever before in its new full metal incarnation. The transformation from the resin model GA-2100 also gives it a more polished appearance, making it wearable with a jacket as well as more casual styles.

The GM-B2100 is not simply a full metal version of a previous hit model. This latest addition to the series serves to expand the full-metal G-Shock lineup as well as adding a new variation to the 2100 series at the same time. This is possible thanks to the G-Shock’s continuing evolution over the years since it was first released. Casio has continued to evolve the functions of the watch as well as regularly updating designs to ensure that the series has maintained its contemporary feel since the release of the first watch in 1983. The GM-B2100 is the most advanced model in the G-Shock lineup so far—one that whets the appetite for further evolutions and developments to come. It lives up to its designers’ aspirations that the series will develop into a “next-generation masterpiece.”

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